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Chemical formulae and chemical equations

In this section you will be tested on your ability to:

1.21 write word equations and balanced chemical equations to represent the reactions studied in this specification
1.22 use the state symbols (s),(l),(g) and (aq) in chemical equations to represent solids, liquids, gases and aqueous solutions respectively
1.23 understand how the formulae of simple compounds can be obtained experimentally, including metal oxides, water and salts containing water of crystallisation
1.24 calculate empirical and molecular formulae from experimental data
1.25 calculate reacting masses using experimental data and chemical equations
1.26 calculate percentage yield
1.27 carry out mole calculations using volumes and molar concentrations

Section notes


Investigations




Resources

Textbook pages:

  • formulas and equations: pages 33 to 38 (chapter 5)
  • empirical and molecular formula: pages 182 to 184 (chapter 22)
  • mass mass calculations: 187 to 189 (chapter 23)
  • gas and mole calculations: 190 to 192 (chapter 23)
  • concentrations and solutions: 209 to 214 (chapter 26)

Tutorials on balancing equations

Balancing equation
balancing chemical equations
try this one
an easy balancing equations game
and another one

Worksheets





Animations
making a solution